Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.atnf.csiro.au/people/Ray.Norris/papers/n217_preprint.pdf Дата изменения: Fri Apr 25 03:59:44 2008 Дата индексирования: Tue Oct 2 17:19:44 2012 Кодировка: Поисковые слова: rigel

In Search of Aboriginal Astronomy
When the British First Fleet arrived in Australia in 1788, their navigators probably knew less about the southern sky than many of the Aboriginal people who they drove from their land. Sadly, nobody thought to ask. The British occupying force wasn't interested in the many rich and vibrant Aboriginal cultures, each with its own customs, folklore, and language. Only recently have most of us appreciated the deep vein of astronomy threading through the Aboriginal stories and ceremonies. With hindsight, we shouldn't be surprised. To those living in Australia thousands of years ago, under the magnificent river of the Milky Way threading through a coalblack sky, the heavens were an integral part of their world. It would have been obvious that particular stars were visible only at certain times of the year and would help navigation through the cool of the night. Even more important would be the belief, shared by most Aboriginal cultures, that the world was created in the "Dreaming" by ancestral spirits who have left their mark all around us. Those who can understand these symbols have a complete understanding of the world and the rules by which one should live - a sort of user manual for living. The night sky would be an important chapter of this manual. Since the 50,000 year-old Aboriginal cultures are far older than Stonehenge or the Pyramids, it is sometimes said that "the Australian Aborigines were the world's first astronomers". Is this statement correct? Quite apart from the assumption of a static culture, the word "astronomy" implies more than just recognising a few stars. It implies a quest to understand the patterns in the sky, the motion of the Sun and Moon, phenomena like eclipses, and whether events in the sky are connected to those on Earth. Can we find evidence for such a deep interest amongst traditional Aboriginal people?

Sun, Moon, and eclipses
The Yolngu people, in the far north of Australia, tell how Walu, the Sun-woman, lights a fire each morning, bringing us dawn. She decorates herself with red ochre, some of which spills onto the clouds, colouring the sunrise. Then she carries her blazing torch across the sky from east to west, creating daylight. As she descends to the western horizon, spilling red ochre at sunset, she extinguishes her torch, and starts the long journey underground back to the morning camp in the east. The Moon, named Ngalindi in the Yolngu language, was a fat lazy man (corresponding to the full Moon) with two wives and two sons, whom he expected to feed and look after him. He became angry with his sons for not sharing their food, and killed them. When his wives found out, they attacked him with their axes, chopping bits off him, giving us the waning Moon. While trying to escape by following the Sun, he climbed a tall tree, but was mortally wounded, and died (the new Moon). After remaining dead for 3 days, he rose again, growing fat and round (the waxing Moon), until, after two weeks his wives attacked him again. To this day, the cycle continues every month.


The Yolngu stories even explain why the Moon is associated with tides. When the tides are high, the water pours into the Moon as it rises, creating a full Moon. As the water runs out of the Moon, the tides fall. Then the tide rises once more, refilling the Moon. So, although the mechanics are a little different from our modern version, this story shows that traditional Yolngu people fully understood the relationship of the Moon to the tides. This depth of knowledge is reflected in stories about eclipses. The Warlpiri people say a solar eclipse happens when the Sun-woman is hidden by the Moon-man as he makes love to her. On the other hand, a lunar eclipse occurs when the Moon-man is pursued and overtaken by the Sun-woman. These two stories demonstrate that traditional Aboriginal people had already figured out that eclipses were caused by a conjunction between the Sun and Moon moving on different paths across the sky, occasionally intersecting. Nor is this understanding confined to the Warlpiri people. The eccentric Englishwoman Daisy Bates, living in the desert in her starched blouse and lace-up boots, recounted primly how, during the solar eclipse of 1922, the Wirangu people told her that the eclipse was caused when the Sun and Moon became "guri-arra ­ husband and wife together." Just a few kilometres from the centre of Sydney hides Ku-Ring-Gai Chase National Park, once home to the Guringai people, who have left behind thousands of beautiful sacred rock engravings depicting the Dreaming ancestors, and images of the animals and fish that abound in and around the Park. Fig 1 here. Some of these images show a man and woman reaching up to a boomerang in the sky. But is it a boomerang? Boomerangs rarely have pointed ends, and usually have two straight lengths rather than a single curved crescent. And how often do a man and woman reach up towards a boomerang sailing above their heads? It seems to me that these shapes are much more likely to be the crescent Moon. Perhaps it may even depict an eclipse, which may then explain why the man is standing in front of the woman, partly obscuring her ­ a feature unusual in these rock carvings.

Stars and Calendars
Bill Yidumduma Harney of the Wardaman people once told me "the law is written in the stars." As an elder, he teaches children how to read the sky, reminding them of the stories and laws that govern Aboriginal life. For example, the stars we call Orion are seen by Yolngu people as a canoe bearing three brothers who were banished to the sky for illegally eating a forbidden fish. Fig 2 here. Close by is the group of stars we call the Seven Sisters, or the Pleiades. In the traditions of several Aboriginal groups, the Pleiades are a group of sisters chased by a young man in Orion. This similarity between Aboriginal and Greek mythology persuaded early anthropologists that there must have been extensive prehistoric cultural contact between Aboriginal and European people. Today, we are pretty


certain that no such contact took place. Instead, Aboriginal people independently devised the stories ­ a sort of cultural convergent evolution. Perhaps this isn't so surprising, when you see the group of pretty starlets pursued by the mighty stars of Orion. Aboriginal calendars tend to be more complex than European ones, and are often based on six seasons, sometimes marked by the heliacal rising of stars. For example, the Pitjantjatjara people mark the start of Nyinnga (winter) by the rising of the Pleiades in the dawn sky. Just as importantly, the appearance of a star or constellation can signal the time to move to a new food source. The appearance of the Mallee-fowl constellation (Lyra) in March warns the Boorong people in Victoria that the Mallee-fowl are about to build their nests, and her disappearance in October tells them that the eggs are laid and are ready to be collected. Some sky patterns are marked by dark clouds rather than stars. Next to the Southern Cross (a possum in a tree, according to the Boorong people) is the dark cloud of interstellar dust that we call the Coalsack. To the Wardaman people, it's the head of a lawman keeping an eye on us, but to many other groups right across Australia, it's one of the best known Aboriginal constellations ­ the Emu in the Sky. The Coalsack is its head, and its neck, body, and legs stretch along the Milky Way right through Scorpius. It's a spectacular sight ­ far better than the contrived European constellations that most of us grew up with. Once you've seen it, the Milky Way will never look the same again. In Ku-Ring-Gai Chase National Park is a rock engraving of an emu, which looks much more like the Emu in the Sky than a real emu. A few years ago, Sydney academic Hugh Cairns pointed out that the engraving is oriented to line up with the Emu in the Sky. Astonishingly, the Emu in the Sky stands above her portrait, in the correct orientation, at just the time when the real-life emus are laying their eggs. Fig 3 here.

The Planets
The silvery glow of Venus, the Morning Star, must be one of the most spectacular sights in the sky. Yolngu people call her Banumbirr, and tell how she came across the sea from the east in the Dreaming, naming animals and landscape. After crossing the shoreline, she continued westwards across the land, creating one of the "songlines" which are still important in Aboriginal cultures. In an important and beautiful "Morning Star Ceremony", Banumbirr helps earthly Yolngu people communicate with their ancestors with the aid of a "Morning Star Pole". After starting at dusk, the ceremony continues through the night, reaching a climax as Banumbirr rises before dawn. Below her, say Yolngu people, is a rope which carries the messages, and which prevents her from ever rising high in the sky. I suspect this faint line in the sky is what astronomers would call zodiacal light, caused by dust in the plane of the solar system. In today's polluted skies it's hidden from most of us, but is still easily visible in the clear dark skies and low latitude of northern Australia. Fig 4 here.


We can learn two important things from the Morning Star ceremony. One is that Yolngu tradition includes the knowledge that Venus never moves far from the Sun, which is explained by a rope binding the two bodies together ­ a bond that Isaac Newton later called "gravity". The other is that since the Morning-Star ceremony needs to be planned, and Venus rises before dawn only at certain times of the year, Yolngu people also keep track of the path of Venus well enough to predict when to hold the Morning Star Ceremony.

Astronomical Measurements
Occasionally I am told something like: "Of course, the Aborigines don't do astronomy ­ they can't even count beyond five." This belief is even supported by one of my anthropology textbooks which confidently asserts that no Aboriginal language has a word for a number greater than four. So I was fascinated to watch a group of Tiwi kids playing in a waterhole, competing to see who could hold their breath longest underwater. They started counting: "Natinga, Jirara, Jiraterima..." What would happen when they reached five? Would they abandon the game? Switch to English? Of course not. They kept counting all the way up to about 70, all in the Tiwi language. Sadly, this myth about innumeracy in Aboriginal cultures persists even amongst people who should know better, even though other anthropologists have carefully documented the various Aboriginal number systems. Such ingrained attitudes state equally misleadingly that Aboriginal people ``don't measure things'' or "don't ask questions", and so would not be interested in careful astronomical measurements. I prefer to stick to the evidence. Fig 5 here. Which brings me to the "Stonehenge Hypothesis". Can we find any evidence amongst Aboriginal cultures that careful observations were made, records kept, or structures set up to point to the rising and setting places of heavenly bodies? Fig 6 here. Maybe. On the dreamy banks of the Murray River, north of Adelaide, is a site called "Ngaut Ngaut", where the Nganguraku people engraved images of the Sun and Moon. Next to these engravings are a series of dots and lines carved in the rock. The traditional owners say these depict the "cycles of the Moon". How do they know? Such knowledge is usually passed through generations from father to son, and from elder to novice at initiation ceremonies. However, these ceremonies were banned, along with the Nganguraku language, by Christian missionaries over a hundred years ago, so only this fragment of culture has survived. The rich record engraved on the walls of Ngaut Ngaut has so far defied attempts at decoding. Perhaps one day we'll succeed, but for the moment we must label it as intriguing, but not conclusive, evidence of Aboriginal astronomy. Fig 7 here. What about structures that mark rising and setting positions? The Wurdi Youang stone arrangement in Victoria is an impressive egg-shaped ring of stones, about 50m in diameter, with its major axis almost exactly East-West. It was built by the


Wathaurung people before European settlement, but all records of its use have now been lost. At its western end, at the highest point of the ring, is an eye-catching group of three waist-high stones. My colleague John Morieson has pointed out that if you stand at these three large stones, some small outlying stones mark the position on the horizon where the sun sets on midwinter's day, on midsummer's day, and at the equinox. A recent survey has confirmed these orientations, but a sceptic might still raise some doubts. First, the outliers are only accurate to a few degrees ­ could these alignments have occurred by chance? Second, although the stones of the circle are large and embedded in the rock, the outliers are small and could have been moved. Third, besides the outliers indicating the solstices and equinox, there is an additional outlier whose significance is unknown. One piece of additional evidence to support Morieson's suggestion was discovered while making the composite picture shown in Fig. 7: the solstices are not indicated solely by the outliers, but also by the fairly straight lines of the ring of stones itself. The best way to confirm this astronomical hypothesis would be to find another site with similar astronomical alignments. We know of other stone arrangements in Victoria which point towards the cardinal points (north, south, east, and west) and so it's pretty certain that the Aboriginal people hereabouts knew these directions fairly accurately, presumably by observing celestial bodies, since they didn't have compasses. But are there other sites which point to the position of the solstice, or equinox? We're working on it. So back to the big question: were Aboriginal people doing astronomy hundreds or thousands of years ago? The growing body of evidence is that traditional Aboriginal people were deeply fascinated by the sky and the motion of the bodies across it, and their astronomical knowledge was far richer and deeper than is usually appreciated. So in that sense, yes. However, the evidence for actual measurements or records remains unproven, although the clues are sufficiently tantalising to fuel the hunt for more. The search continues. Acknowledgement This project is dedicated to the hundreds of thousands of Indigenous Australians who lost their lives after the British occupation of Australia in 1788. I am indebted to the Indigenous groups who have welcomed us onto their land, and I especially thank the elders and people of the Yolngu community at Yirrkala, NT. I also thank my collaborators Hugh Cairns, Paul Curnow, Ian Maclean, John Morieson, Barnaby Norris, and Cilla Norris.


Figures

Fig 1: An engraving from Ku-Ring-Gai Chase National Park, showing a man and woman reaching up to a crescent.


Fig 2: The Yolngu constellation of Djulpan, known to Europeans as Orion. Betelgeuse is the bow of a canoe, Rigel the stern, and the three stars of Orion's belt are the brothers sitting in it. The Orion Nebula is the fish still trailing in the water on its line.


Fig 3. The emu in the sky above her engraving in Ku-Ring-Gai Chase National Park, at the time when emus are laying their eggs. This image won a Eureka prize for photographer Barnaby Norris.


Fig. 4: A morning star pole. The tuft of Magpie-goose feathers at the top represents Venus, and the other feathers represent nearby stars, and other clans.


Fig. 5: Tiwi kids counting who could hold their breath longest underwater.

Fig. 6: The carvings in Ngaut Ngaut, said to represent lunar cycles.


Fig. 7: The view across the Wurdi Youang stone arrangement showing the positions of the setting Sun at the solstices and equinoxes. Composite image made from originals by Ray Norris and John Morieson.